Methods for treating a hollow anatomical structure

Abstract

A working end of a catheter includes at least one therapeutic element, such as a resistive heating element, usable to deliver energy for ligating, or reducing the diameter of, a hollow anatomical structure. In certain examples, the catheter includes a lumen to accommodate a guide wire or to allow fluid delivery. In certain embodiments, a balloon is inflated to place resistive element(s) into apposition with a hollow anatomical structure and to occlude the structure. Indexing devices and methods are also disclosed for successively treating portions of the hollow anatomical structure. In certain examples, marks along the catheter shaft provide visual verification to the physician of the relative position of the therapeutic element of the catheter. Embodiments of indexing devices may include pairs of rings and/or hinged arms that move a catheter a desired indexed position between successive treatments.

1. A method for treating a blood vessel, the method comprising:
 inserting a flexible elongate device into a blood vessel of a patient;
 the elongate device having a shaft and an elongate, electrically driven heating element at a distal portion of the shaft; and 
 the heating element being insulated to prevent electrical contact and electrical conduction with tissue; 
 
 placing the heating element in a first treatment segment of the blood vessel; 
 applying energy to the blood vessel with the heating element for a first dwell time while the heating element remains stationary in the first treatment segment, to reduce the size of the blood vessel lumen to a desired degree in the first treatment segment; 
 moving the heating element along the blood vessel lumen to one or more additional sequential treatment segments of the blood vessel wherein each additional sequential treatment segment comprises a new treatment portion and an overlap portion that overlaps with the preceding treatment segment, each additional sequential treatment segment indicated by an index marking marked on the flexible elongate device; and 
 applying energy to the blood vessel with the heating element for corresponding additional dwell times while the heating element remains stationary in each of the one or more additional sequential treatment segments, to thereby re-treat the blood vessel lumen in the overlap portion and reduce the size of the blood vessel lumen to a desired degree in the new treatment portion; 
 wherein the one or more additional sequential treatment segments comprises a final treatment segment indicated by a final treatment marking on the elongated device. 
 
     
     
       2. The method of  claim 1 , wherein the index markings are spaced apart corresponding to the length of the new treatment portion. 
     
     
       3. The method of  claim 1 , further comprising treating the blood vessel at a rate of approximately 9-15 centimeters of the vessel per minute. 
     
     
       4. The method of  claim 1 , wherein each additional sequential treatment segment overlaps the preceding treatment segment by 1% to 15%. 
     
     
       5. The method of  claim 4 , wherein the treatment segments are each from 2 to 10 centimeters in length. 
     
     
       6. The method of  claim 1 , wherein the heating element comprises a resistive coil. 
     
     
       7. A method for treating a blood vessel having a lumen and an inner wall, the method comprising:
 inserting an elongate device into the blood vessel;
 the elongate device having a shaft and an elongate, electrically driven heating element at a distal portion of the shaft; and 
 the heating element being insulated to prevent electrical contact and electrical conduction with tissue; 
 
 moving the elongate device along the lumen of the blood vessel toward a first treatment segment of the blood vessel; 
 placing the heating element in the first treatment segment of the blood vessel; 
 heating the inner wall of the blood vessel with the heating element for a first dwell time while the heating element remains stationary in the first treatment segment, to reduce the size of the blood vessel lumen in the first treatment segment to a desired degree; 
 moving the heating element along the lumen of the blood vessel to a second sequential treatment segment of the blood vessel indicated by an index marking marked on the elongate device; 
 heating the inner wall of the blood vessel with the heating element for a second dwell time while the heating element remains stationary in the second treatment segment, to reduce the size of the blood vessel lumen in the second treatment segment, wherein the second treatment segment comprises a new treatment portion and an overlap portion that overlaps with the first treatment segment; 
 moving the heating element along the lumen of the blood vessel to a final sequential treatment segment of the blood vessel indicated by a final marking on the elongate device; and 
 heating the inner wall of the blood vessel with the heating element for an additional dwell time while the heating element remains stationary in the final treatment segment, to reduce the size of the blood vessel lumen in the final treatment segment to a desired degree. 
 
     
     
       8. The method of  claim 7 , wherein heating the inner wall of the blood vessel comprises doing so at a rate of approximately 14-42 centimeters of the vessel per minute. 
     
     
       9. The method of  claim 7 , wherein the second sequential treatment segment overlaps the first treatment segment by 1% to 15%. 
     
     
       10. The method of  claim 9 , wherein the treatment segments are each from 2 to 10 centimeters in length. 
     
     
       11. The method of  claim 7 , wherein the heating element comprises a resistive coil. 
     
     
       12. A method for treating a blood vessel having an inner wall, the method comprising:
 inserting an elongate device into the blood vessel, the elongate device having a shaft and an elongate heating element; 
 placing the heating element in a first treatment segment of the blood vessel; 
 heating the inner wall of the blood vessel with the heating element for a first dwell time while the heating element remains stationary in the first treatment segment; 
 moving the heating element along the blood vessel to at least a second treatment segment of the blood vessel indicated by an index marking marked on the elongate device, wherein each treatment segment after the first comprises a new treatment portion and an overlap portion that overlaps with the preceding treatment segment; 
 heating the inner wall of the blood vessel with the heating element for a second dwell time while the heating element remains stationary in the second treatment segment; 
 moving the heating element along the lumen of the blood vessel to a final treatment segment of the blood vessel indicated by a final marking on the elongate device; and 
 heating the inner wall of the blood vessel with the heating element for a final dwell time while the heating element remains stationary in the final treatment segment. 
 
     
     
       13. The method of  claim 12 , wherein the duration of each of the first and second dwell times are the same. 
     
     
       14. The method of  claim 12 , wherein at least one of the durations of one of the first, second, and final dwell times differs from the duration of the other two dwell times. 
     
     
       15. The method of  claim 12 , further comprising treating additional treatment segments, in addition to the first, second, and final treatment segments. 
     
     
       16. The method of  claim 15 , wherein each treatment segment is adjacent the previous segment, and the first, second, and additional treatment segments are treated sequentially before the final treatment segment. 
     
     
       17. The method of  claim 12 , wherein inserting the elongate device comprises inserting the elongate device through an introducer sheath having a reference location. 
     
     
       18. The method of  claim 17 , wherein the index marking marked on the elongate device comprises a first index marking and the elongate device further comprises a second index marking also marked on the elongate device, wherein moving the heating element along the blood vessel to at least a second treatment segment of the blood vessel is facilitated by withdrawing the elongate device to move the first index marking in a distal direction from the reference location to thereby position the second index marking at the reference location. 
     
     
       19. The method of  claim 18 , wherein the first and second index markings are consecutive and the consecutive index markings become visible as the elongate device is withdrawn from the introducer sheath to treat consecutive treatment segments.